[Debian-science-sagemath] Sage 7.6

[Tobias Hansen]

Hi all,

sage 7.6 was released yesterday. It's already packaged and the main
blockers are that jupyter-core, jupyter-notebook and ipywidgets (and
maybe ntl) need to be updated and several floating point exceptions
during doctesting.

Gordon, could you update the three jupyter packages or do you want
someone else to do it? For now it would be enough to have something in
git so we can test and then eventually upload everything to experimental.

I have no idea yet where the floating point exceptions are coming from.
Since not that much seems to have changed, maybe it is due to the
updated ecl and maxima.

Best,
Tobias